Abstract
A blue ceramic coating was prepared on 5052 aluminum alloy by micro-arc oxidation in the manuscript. We systematically investigated the effects of the Co(OH)2 concentration and the applied voltage on the microstructure and the corrosion resistance. The OM, SEM and XRD were employed to characterize the macrostructure, microstructure and phase structure, respectively. The electrochemical corrosion resistance of coatings was measured by an electrochemical workstation in 3.5 wt% NaCl solution. The results show that the phase structure is mainly compose of γ-Al2O3. As the Co(OH)2 concentration and voltage increased, the blueness degree of coatings gradually deepen, and the color is the darkest when added 3.0 g/L Co(OH)2. Meanwhile, the surface tended to close and became denser. The results show that the corrosion resistance of ceramic coating is best with 1.0 g/L Co(OH)2 when the voltage was 140 V. We believe that the micro-arc oxidation technology of blue ceramic coating will have a wide range of applications in building materials and instrumentation industries as its gorgeous color and decorative function.
| Original language | English |
|---|---|
| Pages (from-to) | 121-126 |
| Number of pages | 6 |
| Journal | Cailiao Daobao/Materials Review |
| Volume | 31 |
| Issue number | 5 |
| DOIs | |
| Publication status | Published - 25 May 2017 |
Keywords
- Aluminum alloy
- Blue ceramic coating
- Electrochemical corrosion
- Micro-arc oxidation
- Microstructure